"STAR limit exceeded" means DHE is not valid as a final waypoint if you want to land at EDDH. Have a look at arrivals (STARs) map for EDDH to see what waypoints initiate a STAR, as one of them should be the last item of your plan.

By the way, it looks like you tried to list individual waypoints of the STAR - this is incorrect. Either skip the STAR at all or provide it's name instead.

As an aside, I see the real world UAL74 flights join via GRONY and use the route GRONY UM105 EEL UN125 REVLA T907 SORUN T903 RIBSO to get into Hamburg. They join GRONY via the UN873 or UL603 depending on the exit point from the NAT route.